﻿using System;
using System.Numerics;
class FibonacciNumbers
{
    static void Main()
    {
        int number;
        Console.Write("Please enter sequence lenght: ");
        do
        {
            while (true)
            {
                try
                {
                    number = int.Parse(Console.ReadLine());
                    break;
                }
                catch (Exception)
                {
                    Console.Write("Please re-enter lenght: ");
                }
            }
        } while (number <= 0);
        BigInteger preprevfibomember = 0;
        BigInteger prevfibomember = 1;
        BigInteger fibomember = 0;
        for (int counter = 1; counter <= number; counter++)
        {
            Console.Write("{0}, ", fibomember);
            preprevfibomember = prevfibomember;
            prevfibomember = fibomember;
            fibomember = (prevfibomember + preprevfibomember);
        }
        Console.ReadLine();
    }
}

